1 Introduction

The Henize sample of S stars (as listed in Stephenson 1984) comprises S stars south of $\delta=-25^\circ$ and brighter than R=10.5, and is supposedly complete. A large-scale study has been devoted to this sample in order to better characterize the two families of S stars, the intrinsic S stars (bona fide thermally-pulsing asymptotic giant branch stars) and the extrinsic S stars (binary masqueraders). The data are presented in this paper; for their analysis the reader is referred to Van Eck & Jorissen (2000; hereafter Paper III).

Section 2 presents the radial velocity data along with 5 new orbits; the Geneva photometry and JHKL SAAO photometry are presented in Sects. 3 and  4, respectively. Estimates of the bolometric magnitudes are derived in Sect. 5. Section 6 discusses the IRAS fluxes available for Henize S stars, and Sect. 7 presents the method used to reduce 158 low-resolution spectra and to derive band-strength indices. All these data, along with the results of the multivariate classification performed in Paper III, are listed in accompanying tables.